Archaeological findings suggest the road was in regular use in the 3rd millennium BC, connecting Central Asia with Mesopotamia.
[9] The road continued to Madharustan and finally exited the Hulwan pass at the town of Kirind and the village of Khushan.
[10] From Kirmanshah the road continued to Hamadan and Sivah, turned north to Rayy, and from there passed east into the province of Qumis.
[11] The road was the main lifeline of Qumis, and most of the province's towns were located along its course: Khuwar, Qasr or Qariyat al-Milh (the "Salt Castle"), Ras al-Kalb ("Dog's Head", identifiable with Lasgird), Samnan, Damghan, al-Haddadah ("the Forge") or Mihman-Dust, and Bistam.
[13] Shortly after Nishapur, at Qasr al-Rih ("Castle of the Wind"), the road divided again into two branches leading southwest and northeast.
[16] From Samarkand, the road crossed the Sughd River and led to the town of Zamin in Usrushana, east of the local capital, Bunjikath.